1. Field of the Invention
The present invention relates to novel monomethyl malonate derivatives and a production process thereof. The novel monomethyl malonate derivatives serve as precursors for indanonecarboxylic acid esters which have a halogen atom in the indanone ring and are useful as synthetic intermediates for insecticides.
2. Description of the Related Art
Indanonecarboxylic acid esters each having a halogen atom in the indanone ring are useful as synthetic intermediates for insecticides (e.g., U.S. Pat. No. 5,869,657). Certain production processes are known for the production of these indanonecarboxylic acid esters. PCT International Publication Number WO00/10963, for example, discloses a process for preparing an indanonecarboxylic acid ester by reacting a halogenated anthranilic acid derivative with sodium nitrite or methyl nitrite to yield a diazonium salt, reacting the diazonium salt with an acrylic acid derivative in the presence of a palladium-containing catalyst to yield substituted cinnamic acid and cinnamic acid ester, hydrogenating the same by the catalysis of a hydrogenating catalyst to yield a substituted arylpropionic acid, and subjecting the substituted arylpropionic acid to ring-closing reaction in the presence of a base to yield an indanonecarboxylic acid ester. This process, however, is not suitable for commercial production, since the process uses, as an intermediate, a diazonium salt which is difficult to handle safely.
PCT International Publication Number WO 95/29171 discloses a process for preparing an indanonecarboxylic acid ester by subjecting a para-substituted phenylacetyl halide to Friedel-Crafts reaction with ethylene to yield a substituted tetralone, subjecting the substituted tetralone to ring-opening reaction in the presence of a peroxycarboxylic acid to yield a substituted arylpropionic acid, esterifying the substituted arylpropionic acid, and subjecting the ester to ring-closing reaction in the presence of a base to thereby yield a substituted indanonecarboxylic acid ester. This process, however, is not suitable for commercial production from the viewpoint of safety, since the process uses a peroxide for the ring opening of the substituted tetralone.
Japanese Unexamined Patent Application Publication No. 05-25164 discloses a process for preparing an indanonecarboxylic acid ester by esterifying a substituted indanone typically with dimethyl carbonate. The publication discloses, as an example, a process for preparing methyl indanonecarboxylate by reacting 5-chloroindanone with dimethyl carbonate in the presence of sodium hydride. However, this process only achieves a yield as low as 50% or less.
Monoethyl phenylmalonate is known as a malonic acid monoester derivative (J. Org. Chem., 65, 2000, 5834; and J. Amer. Chem. Soc., 74, 1952, 5897). Diethyl benzylmalonate and diethyl 3-benzylmalonate are known as malonic acid diester derivatives (J. Med. Chem., 13, 1970, 820; and Synthesis, 6, 1987, 565). However, these documents fail to describe monomethyl 3-halobenzylmalonates and production thereof.